Fuel cells are a highly efficient and pollution free power generating device directly converting chemical energy of reactants to electrical energy, and are currently used in power plants for households or electric vehicles, and are also used in various fields for industrial uses, military uses and the like. Fuel cells are divided into a molten carbonate fuel cell (MCFC), a solid oxide fuel cell (SOFC), an alkali fuel cell (AFC), a phosphoric acid fuel cell (PAFC), a polyelectrolyte fuel cell (PEMFC), a direct methanol fuel cell (DMFC) and the like depending on an electrolyte, an operating temperature and a fuel type. Among these fuel cells, a polyelectrolyte fuel cell has excellent energy conversion efficiency and is capable of obtaining high current density even at low temperatures, and therefore, development thereof for application in various fields have been actively progressed.
Performance of a polyelectrolyte fuel cell is highly influenced by performance of a membrane electrode assembly catalyst of the fuel cell, and platinum (Pt), one of the raw materials, greatly affects fuel cell costs due to its very high price. Accordingly, researches and developments on catalysts for enhancing fuel cell performance and reducing costs have been substantially carried out.
For increasing activity of a fuel cell catalyst, researches on preparing platinum in a nano size and researches on supporting platinum in a highly dispersed manner and in a high ratio on carbon having a high surface area have been progressed. In addition, researches on using an alloy with other metals have been carried out in order to reduce platinum content, which accounts most of fuel cell costs.